Sexually transmitted diseases (STDs) and their sequelae of ectopic pregnancy and pelvic inflammatory disease (PID) have been documented as the major cause of female infertility. Sexually active adolescent females are recognized as the most at risk population for PID and STDs including C. trachomatis and N. gonorrhoeae. Recognition of AIDS in the heterosexual population underlines its potentially enormous impact on young adults and their children. Knowing that sexually related issues including decisions regarding sexual debut, contraception, choice of partners and fertility planning in conjunction with the knowledge that high rates of STDs occur among adolescents, it is imperative that the adolescent population is targeted. In addition, with an estimated incubation period from 2-7 years or more for AIDS, it is apparent that many HIV infections occur during adolescence since there is a 10 fold increase in AIDS among 20-24 year olds compared to 15-19 year olds. We propose to examine the psychological correlates of sexual behaviors among youth in detention which place them at risk for acquisition of STDs including HIV infections. We have chosen youth in detention since they are the most at risk youth for STDs and AIDs because of their sexual and drug behaviors. We propose to examine: 1) prevalences/patterns of sexual behaviors; 2) the cross-sectional relationship between stated intent to engage in the preventive behavior and an expanded Health Belief Model (HBM); 3) the longitudinal relationship between stated intent and self report of actual sexual behaviors 3 months later; and 4) the independent relationship between a current STD and the HBM as well as self reported current sexual behaviors by screening the study group with STD cultures. The understanding of these behaviors and interrelationships form the basis for planning interventions with this high risk population of youth.